层状Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2正极材料的合成与电化学性能研究

Synthesis and Electrochemical Characterization of Layered Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2 Cathode Material

采用共沉淀-喷雾造粒法制备前驱体,于750℃在空气中煅烧20h合成出层状Li(Ni1/3Co1/3Mn1/3)O2正极材料,并用XRD,SEM,粒度分析和电性能测试考察了所得材料结构、形貌及电化学性能.本层状Li(Ni1/3Co1/3Mn1/3)O2正极材料具有α-NaFeO2结构,六方晶系,R3m空间群,其晶胞参数为a=0.2865nm,c=1.4238nm.当材料分别在2.8～4.2,2.8～4.5V间进行充放电时,其首次放电容量分别为173.5和185.4mAh?g-1,首次充放电效率分别为90%和83.8%,40次循环后容量保持率分别为96%和84%.

The precipitate-spray method was used to prepare the precursor. The layered Li（Ni1/3Co1/3Mn1/3）O2 cathode material for lithium ion batteries was synthesized in air atmosphere at 750℃ for 20 h from the precursor. XRD analysis, SEM and electrochemical tests were used to characterize the structure, appearance and electrochemical performances of the aimed material. The hexagonal layered LiNi0.5Mn0.5O2 has an α-NaFeO2 structure and space group R3m with lattice parameters of α=0.2865 nm, c= 1.4238 nm. Initial discharge capacities of 173.5 and 185.4 mAh·g^-1 were obtained in the range 2.8～4.2 and 2.8～4.5 V, respectively. 96% and 84% of the initial discharge capacities were reserved after 40 cycles at each chargedischarge voltage.